Production of enantiomerically enriched ortho-substituted .alpha

Details Production of enantiomerically enriched ortho-substituted .alpha Production of enantiomerically enriched ortho-substituted .alpha

1995-02-17

1997-07-08

Conrad, Joseph

Organic compounds -- part of the class 532-570 series

Organic compounds

Carboxylic acid esters

568702, 568707, C07C22934

Patent

active

056463308

ABSTRACT:
A method of producing compounds of formula I ##STR1## wherein one of R.sub.1 and R.sub.2 is selected from --OH, --SH, and --NHR.sub.7 ; and the other of R.sub.1 and R.sub.2 is selected from H, --OH, --SH, --NHR.sub.7, and R.sub.8 ; R.sub.3 and R.sub.4 are each independently selected from R.sub.8 ; n and m are each independently 3; and each R.sub.5 and each R.sub.6 is independently selected from --OH, --SH, --NHR.sub.7, and R.sub.8 ; and R.sub.8 is as detailed in the specification;
in enantiomerically enriched form, comprising reducing a compound of formula II ##STR2## wherein R.sub.1 -R.sub.6 are defined as in formula I, in the presence of B-haloisopinocampheylborane.

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